This invention relates to base frames and base linkages for power driven reclining lift chairs.
In reclining chairs a tiltable back and seat are driven between an erect and a reclined position, and a leg or foot rest is driven between a retracted and an extended position. A lift chair is powered between a normal seat position and an elevated forwardly inclined position. In various prior art reclining lift chairs the speed of motion or velocity of the back or seat or the leg rest as sensed by the chair occupant changes or varies during the course of movements in the elevating or reclining mode. Additionally, in some prior art chairs there is some dwell that occurs at certain points in the motion. Because of the attitude of the flying links in prior art chairs there is no vertical tie in the reclining hinge, and the seat is unstable. In the prior art devices the linkages are not always force-loaded, and accordingly there is a dwell and hence intermittent motion prior to full loading of the links. The dwell and velocity changes make the chairs perform with erratic, non-uniform movements that are disconcerting to the elderly users of the chairs. Play in the driving linkages of the prior art chairs also contributes to the non-uniform motion of the chairs.